Dynamics Parametrization and Calibration of Flexible-Joint Collaborative Industrial Robot Manipulators

Figure 5

Schematic representation of the Inverse Dynamics Identification Model with Weighted Least Squares (IDIM-WLS) estimation and rotor dynamics compensation procedure. The estimation trajectory sends desired angular positions to the controller, which generates torque commands to the robot. The angular positions of the links and rotors, and , respectively, are measured and then filtered to generate smoothed estimates and time-derivatives , , , and . The rotor quantities are passed to the Rotor dynamics compensation, and the link quantities are passed to the Linearized dynamic model. The Rotor dynamics compensation augments the measured current with the rotor dynamics based on (15) to estimate joint torques . The Linearized dynamic model generates regressors for each joint . The joint torque estimates and regressors are filtered and downsampled to generate, respectively, the measurement vector and observation matrix . The measurement vector and observation matrix are passed to the OLS Estimation and WLS estimation procedures. The OLS procedure produces the weighting matrix used in the WLS procedure. Finally, the WLS estimation provides the dynamic parameters estimates .